DE1401300B2 - Servo control of several pressure consumers - Google Patents

Description

3 4

In the switching valves 1 and Γ at 2 the inlet area of the closed position of the locking pieces 4 and at 3 the drain to the consumer and the verification with greater security is to be determined, a sealing piston 18 is provided on the locking piece 4 opposite the valve seat 5 in at the end piece , sealed in a known manner. Both valves will protrude into the inlet cross-section and can be adjusted in axiads at the same time by means of switching magnets 15 in a directional direction.
Switch 16 triggered. In the embodiment according to FIG. 2 is from

A duct to a multi-way switching valve in double design opens into the valve seat 5 or 5 '

Order in the form of an annular channel 6 or 6 'or assumed, the two valves 1 and 1' also

one or more bores which are parallel to one another in their transverse direction in a manner known per se

Section are kept larger than the io can be switched in the inlet direction and together to trigger

into these ring channels opening further connection and only a single connection 19 for

opening 7 and 7 '. The ring channels 6 and 6 'have a pressure consumer, as is the case

thus open in the direction of the pressure consumer from the dotted power curve shows.

and are connected to a measuring line 8. With these valves, too, as in the execution

In this measuring line 8 are measuring elements, preferred example according to FIG. 1, the valve seat 5 with the channel configuration in the form of a double piston 9, provided, arrangement 6, which is connected to the measuring line 8 which controls the pressure in the two valves 1 and 1 ', the cross-section of the channel monitoring. If each of the closure pieces 4 is an arrangement 6 is kept much larger than the wall-free tight or in the right way, z. B. the same cross-section of the feed openings 7, which are actuated in the right direction, then there is in front of the two fronts 20 direction of the servo means feed 2,
surfaces 10 of the double piston 9 no differential pressure. The measuring element in this exemplary embodiment be-The double piston can also be made up of a double piston 9 with the aid of springs, with each central position being transferred. If differential pressure, however, the measuring lines 8 preferably occur above these pressures, the double piston is shifted in the double piston with the help of an adjustable throttle cord or other direction, and there is 25 point 13 interconnected, the transverse of which the cut-off device 11 is set in motion for the cut essential must be kept smaller than shutdown of the valves. . the entire cross section of the opening 7. On this

The shutdown device 11 engages the Meßglie- way, it is possible, preferably by the adjuster 9 via a z. B. in their width adjustable training of this bridging of the measuring lines 8 a recess 12 in order to bridge certain movement tolerances of the 30 directly on the measuring members or on the measuring member 9, measuring members 9. If, for example, at certain movement tolerances as a result of the locking element 4 of the valve 1, a leakage of one valve against the other has occurred, then it is formed in the direction of the same or even to be introduced without the outlet 3 causing a pressure drop, since that is caused by the inlet switching device 11 responds,
side over the smaller opening 7 tapering pressure 35 should also the upper opening position with a medium is limited in its amount depending on the trains such multi-way valve for the respective abandoned lowest response limit of the device. tail 4 are monitored, then also receives

Z. B. on the left side of the measuring element concerned valve seat 5 'a similarly designed

des 9 a lower pressure than on the other side dete channel arrangement 6 'with a smaller connection on

of the measuring element, since the smaller inlet opening 7 40 inlet, which is then also via measuring lines 8 '

of the valve 1 in the measuring line 8 is still on a further measuring element, which is not shown in detail

full control pressure comes into play, it is what comes into play.

However, this channel arrangement 6 'in

Measuring element 9 set in motion. their valve seat 5 'to the already existing one

If one of the switching valves is faulty or not 45 measuring element 9 takes effect, provided that between

switched jointly in good time or both measuring lines then correspondingly fail

for example the release part for this switching valve, valves 17 ', e.g. in the form of non-return valves,

e.g. the switching magnet, and then remains the relevant, which may be provided before moving

Fende locking piece in its lower position lying sequence of the locking pieces 4 or of the

gen, while the other is opened, then 50 valve rods of the closure pieces occur in one

the safety control is also active, and the correct switching rhythm is still activated, so-

the disconnection device 11 is actuated because soon the locking pieces one or the other

also leave here with the opening valve in the measuring switch position. But it can also, from

line 8 sets a pressure reduction and starting in one of the valve positions, the measuring

Whose measuring line existing full control pressure lines are switched over. That way is

remain. it is also possible with multi-way valves to switch both positions

In order to monitor this pressure build-up and reduction directly in the lungs of the closure pieces.

1 sheet of drawings

Claims (7)

Patent claims: 1. Servo control of several pressure consumers in each one servo medium circuit, in particular for the clutch and brake of a press drive, via simultaneous mechanical or Individual switching valves to be triggered by switching solenoids or combined to form a double valve each and individual valves connected in parallel for only one pressure consumer, with measuring lines, from each with one end to a switching valve and the other end to a pressure differential responsive measuring device is performed, the one-sided pressure reduction at a switching valve or a one-sided Pressure build-up in the area of the measuring device assigned to it, a shutdown device triggers, characterized in that each measuring line (8) at the switching valves (1, Γ) with a channel arrangement opening into their valve seats (5, 5 ') in the direction of the pressure consumer (6, 6 ') is connected to which a connection opening (7, 7') to the pressure medium supply space the switching valves (1, 1 ') is connected, the cross section of which is smaller than that of the Channel arrangement (6, 6 ') 2. Servo control according to claim 1, characterized in that the channel arrangement (6, 6 ') is a ring channel. 3. Servo control according to claims 1 and 2, characterized in that as a double piston version formed measuring elements have a preferably adjustable throttle point (13). 4. Servo control according to claims 1 and 2 with multi-way valves for one or both sides pressurized consumers, characterized in that each of the valve seats (5, 5 ') in the consumer direction with one channel arrangement each opening into the sealing area (6, 6 ') is provided, which either on further measuring elements or on the same measuring elements of the first Channel arrangement acts, the first channel arrangement (6) then via valves (17 ') preferably check valves, in which the measuring lines (8 ') are switched off (FIG. 2). 5. Servo control according to claim 4, characterized in that these shut-off valves (17 ') depending on the sequence of movements of the locking pieces, in particular on their linkage, are alternately opened and closed, this operating range by adjustable Attacks is changeable. 6. Servo control according to claim 5, characterized in that special with the valve linkage Control edges are connected to which the measuring lines (8) are brought up for their switching will. 7. Servo control according to one of the preceding claims, characterized in that a sealing piston (18) is arranged on the closure piece (4) in the inlet direction, which is inserted into the Inlet engages in the closed position. The invention relates to a servo control of several pressure consumers in each one servo medium circuit, especially for the clutch and brake of a press drive, mechanically at the same time or individual switching valves to be triggered by switching solenoids or one double valve each combined and parallel-connected individual valves for only one pressure consumer, with measuring lines, from each with one end to a switching valve ίο and with the other end to one on pressure differences responsive measuring device is performed, which in a unilateral pressure reduction on a Switching valve or a one-sided pressure build-up in the area of the measuring device assigned to it a shutdown device triggers. With such safety controls it turns out that before the locking pieces finally close, an overlap in the valve movements is required (e.g. 0.5 mm) to enable the safety controller to d. H. to let the measuring elements respond. This then has the disadvantage that if the sealing point is slightly damaged, the closure pieces in this order of magnitude or in the case of small foreign bodies that are located at these sealing points fix, the valve in question is leaking without the safety device responding fully. This observation is particularly annoying with such valves, in which in the sealing area through Wear changes in the sealing point occur, so that such a valve leaks without There is a possibility of having the safety control respond when the path changes are minor, because both types of switching work depending on the movement of the locking pieces. There is already a safety device for servo controls known in which holes in a Closing piece of the switching valve of a multi-way valve provided with an auxiliary valve release with the Pressure chamber of the auxiliary valve circuit are connected. With such a facility is only a path-dependent one Address possible. This control does not work independently of the path. The invention has for its object to avoid the path dependency and the safety device directly to take effect from the closed position of the locking pieces. According to the invention this is achieved in that each measuring line on the switching valves with a is connected in the valve seats opening out channel arrangement in the direction of the pressure consumer, to which a connection opening to the pressure medium supply chamber of the switching valves is connected, whose Cross section is smaller than that of the channel arrangement. Further details emerge from the subclaims. The exemplary embodiments show how the invention can be carried out in detail with the parts essential for it in the drawing, namely F i g. 1 a control in the section of two individual valves that are triggered together, with normal straight-way valves are used as valves, F i g. 2 two single valves with common actuation as multi-way valves, which are also interconnected in pairs to form a single valve group and can act on a single pressure consumer.